module VCLog

  # A Release encapsulate a collection of {Change} objects
  # associated with a {Tag}.
  #
  class Release

    # Tag object this release represents.
    attr :tag

    # Array of Change objects.
    attr :changes

    #
    # New Release object.
    #
    # @param [Tag] tag
    #   A Tag object.
    #
    # @param [Array<Change>] changes
    #   An array of Change objects.
    #
    def initialize(tag, changes)
      @tag     = tag
      @changes = changes
    end

    #
    # Group +changes+ by type and sort by level.
    #
    # @return [Array<Array>]
    #   Returns an associative array of [type, changes].
    #
    def groups
      @groups ||= (
        changes.group_by{ |e| e.label }.sort{ |a,b| b[1][0].level <=> a[1][0].level }
      )
    end

    #
    # Compare release by tag.
    #
    # @param [Release] other
    #   Another release instance.
    #
    def <=>(other)
      @tag <=> other.tag
    end

    #
    # Convert Release to Hash.
    #
    # @todo Should +version+ be +name+?
    #
    def to_h
      { 'version'  => tag.name,
        'date'     => tag.date,
        'message'  => tag.message,
        'author'   => tag.author,
        'id'       => tag.id,
        'changes'  => changes.map{|change| change.to_h}
      }
    end

  end

end